Bug 1264452

Summary: squid: Incorrect message size checking in HTTP Proxy causes DoS
Product: [Other] Security Response Reporter: Adam Mariš <amaris>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED NOTABUG QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: carnil, henrik, jonathansteffan, luhliari, psimerda, thozza
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: squid 3.5.9 Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2015-10-27 14:31:45 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On: 1264455    
Bug Blocks: 1264449    
Attachments:
Description Flags
Upstream patch none

Description Adam Mariš 2015-09-18 13:36:43 UTC 
Vulnerability in SSL/TLS parser in Squid HTTP Proxy was found caused by incorrect message size checks and assumptions about the existence of TLS extensions in the SSL/TLS handshake message. This can lead to very high CPU consumption (up to and including 'infinite loop' behaviour). Vulnerable versions are 3.5.0.1 to 3.5.8 (inclusive), which are built with OpenSSL and configured for "SSL-Bump" decryption. This can be exploited remotely. Although there is one layer of authorization applied before this processing to check that the client is allowed to use the proxy, the check is considered generally weak.

CVE request:

http://seclists.org/oss-sec/2015/q3/577
Comment 1 Adam Mariš 2015-09-18 13:37:19 UTC 
Created attachment 1074919 [details]
Upstream patch
Comment 2 Adam Mariš 2015-09-18 13:38:43 UTC 
Created squid tracking bugs for this issue:

Affects: fedora-all [bug 1264455]
Comment 3 Adam Mariš 2015-09-21 12:31:15 UTC 
Security Advisory:

http://www.squid-cache.org/Advisories/SQUID-2015_3.txt
Comment 4 Stefan Cornelius 2015-10-27 14:31:45 UTC 
I believe this was introduced via:
http://bazaar.launchpad.net/~squid/squid/trunk/revision/14012

This code never made it into RHEL5, 6, or 7.

Statement:

This issue did not affect the versions of squid as shipped with Red Hat Enterprise Linux 5, 6, and 7.